AstraZeneca AB v. Mylan Pharms. Inc.

Case Name: AstraZeneca AB v. Mylan Pharms. Inc., No. 18CV193, 2022 WL 16857400 (N.D.W.V. Nov. 9, 2022) (Keeley, J.) 

Drug Product and Patent(s)-in-Suit: Symbicort® (budesonide/formoterol); U.S. Patent No. 10,166,247 (“the ’247 patent”) 

Nature of the Case and Issue(s) Presented: Mylan sought approval to market a generic version of AstraZeneca’s Symbicort inhaler. Plaintiff asserted the ’247 patent. Mylan argued that the ’247 patent was invalid for lack of enablement and lack of written description.

Why Mylan Prevailed: The court found the ’247 patent invalid for lack of enablement. Mylan argued that the asserted claims covered “tens of thousands or millions of combinations of different doses of budesonide, different doses of formoterol and all of its salts, and different PVP and PEG grades and concentrations.” In addition, Mylan noted that the specification only taught how to make a limited subset of embodiments; namely, how to reproduce Symbicort and Symbicort-like products. AstraZeneca replied that a skilled artisan would not deviate from the specification’s disclosure, meaning it would not go in search of new stable formulations and, even if she did, any additional screening would be routine. The court found that the broad scope of the claims and the narrow disclosure in the specification supported a non-enablement finding.

The court conducted an In re Wands analysis, which favored Mylan’s arguments. In particular, the prior art provided little guidance; it provided no teaching how the five generically claimed ingredients would interact in suspension formulations or how a skilled artisan might combine them to achieve stable formulations. Further, there was substantial evidence that pMDI suspension formulations were complex and unpredictable, meaning that the predictability of the art (or lack thereof) weighed against enablement. Additionally, although the court noted that the specification included many examples of stable formulations, those embodiments consisting of the same five ingredients and provided teachings for only a small corner of the claimed genus. Finally, the court found that the quantity of experimentation would be undue because the asserted claims encompass tens of thousands of candidate formulations that must be screened for stability and formulating embodiments outside the scope of the disclosed examples would require substantial trial-and-error testing.

Next, the court found the ’247 patent invalid for not meeting the adequate description requirement of Section 112. Mylan argued, as with enablement, that the ’247 patent provided a narrow subset of examples that only describe a fraction of the broad, functionally defined genus recited in the claims. More particularly, the specification would not have led a skilled artisan to believe that the inventors possessed all stable formulations comprised from the five generic ingredients recited in the claims. In response, AstraZeneca argued that the asserted claims were adequately described because the specification “unambiguously identifies that the invention is the novel combination of budesonide, formoterol, HFA 227, PVP, and PEG” and described exemplary formulations. But the court explained that the claims covered a class of at least tens of thousands of candidate formulations and the specification’s examples only describe a single formoterol salt, a single formoterol dose, four budesonide doses, a single PVP grade, and a single PEG grade. Thus, the claims were invalid for lack of written description because the species disclosed in the specification all lie in the same corner of the genus and were insufficient to support the full scope of the claims.